Adding-machine



(No Model.)

W. M. HOWLAND.

ADDING MACHINE,

Patented Dec. 6,1881.

INVENTOR .ATITORNEYIIS WITNESSES NITED STATES PATENT OFFrce.

WILLIAM M. HOVVLAND, OF TOPSHAM, MAINE.

ADDING-MACHINE.

SPECIFICATION forming part of Letters Patent No. 250,541, dated December 6, 1881.

Application filed April 23, 1881. (No model.)

To all whom it may concern:

Be it known that LWM. M. HOWLAND, a resident of Topsham, in the county of Sagadahoo and State of Maine, have invented a new and valuable Improvement in Adding-Machines; and I do hereby declare that the following is a full, clear, and exact description of the construction and operation of the same, reference being had to the annexed drawings, making a part of this specification, and to the letters and figures of reference marked thereon.

Figure 1 of the drawings is a transverse section. Fig. 2 is a side "iew, partly in section, looking through the shield. Fig. 3 is a side view from the other side. Fig. 4 is a detail; Fig. 5, a modification of the pawl.

This invention relates to improvements in adding-machines.

The invention consists in the construction hereinafter set forth.

In the annexed drawings, A is a frame, consisting of base B and posts 0 0. Running from post to post is the axle D, on which are sleeved the wheels E, their number depending on the amount liable to be needed. These wheels are cup-shaped, having a flat head, 0, and ratchetflange e. Secured to the wheel and lying along the tread are the two hooks, F, their hooked endsf being diametrically opposite. On the surface of .the tread are arranged the figures from 1 to 0 four times. G is a lever, having handle 9 and moving in axle D, a pawl, g, attached to said lever, en gagingthe ratchet-flange 6. These wheels, with their levers, are putin place, the hooked endfot' the hook F being turned toward the next wheel.

H is a slotted apron secured to the frame, through the slots h of which the handlesg project. These slots are graduated downward from 1 to 9, and notched as shown.

I is a bar running from the top of one post to that of the other, and having the dependent pins 6, in number equal to the wheels.

At the side opposite to the apron is placed a bar, K, having spring-pawls it playing in the ratchet-rims, and the dependent pins k, similar to pins '6. It will be seen by the location of these pins 6 and I0, and the hooks F, that as awheel turns, when the hook f comes in contact with a pin it is thrown over and catches one of the teeth of the next wheel and moves the wheel one tooth. After passing the pin the spring in the tooth throws it back into position. The position of these hooks is such that it makes each succeeding wheel turn one tooth for ten of that preceding.

For use the wheels are set with a zero on each at the slot between the top of the apron and bar I, and the handles of the levers at the top of the apron-slots. The handle of the unitwheel is brought down to the number on its slot corresponding with the unit of the first number of those to be added. By this the pawl on this handle turns the, wheel as many teeth as units. Then the handle of the tens-wheel is worked the same way, and so on for the first number. For thenext number the handles are returned and the operation continued, and so on for all the numbers which are to be calculated. After all are calculated the number which is under the slot is the sum of the numbers.

It will be seen that when the number ofany two or more digits in order of the same denomination goes over nine it causes the next wheel to be turned one tooth by reason of the engagement of one of the hooks on the first wheel.

Instead of using the drag-pawl g on the levers D the push-pawl 2 may be used.

I am aware that an adding-machine consisting of a series of numbered disks arranged on a shalt and having interlocking pawls is not broadlynew, and I simply lay claim to my special construction.

I claim The frame A,'having the slotted apron H, provided with series of numbers, and bars I and K, having pins i and 7c, in combination with handles G and wheels E, having ratchetflanges c, and spring-hooks 1*, as set forth.

In testimony that I claim the above I have hereunto subscribed my name in the presence of two witnesses.

WILLIAM M. HOWLAND.

Witnesses:

SAMUEL T. WHITE, MARY E. WHITE. 

